The present invention relates to the handling and conveying of optical materials, more particularly the handling of lenses during coating processes.
Frequently, in the course of manufacturing an optical lens it is necessary to deposit a layer of optical coating material, such as for example General Electric SHC 1200 Silicone Hard Coating Resin, upon one or more surfaces of the lens element. A variety of coatings are typically used in the art to achieve the desired optical characteristics of tint, refractive index, and abrasion resistance. In order to assure optical quality, it is desirable to minimize the physical handling of the lens element during the manufacturing and coating processes. However, in the case where relatively hard optical materials are used, for example lenses composed of allyl diclycolcarbonate such as CR-39 manufactured by the Pittsburgh Plate Glass Company, it is frequently difficult to attach or mount handling means to the optical material.
A number of techniques have been used in an attempt to provide a practical solution to the problem of handling thermoset plastic and other lenses. For example, one technique which has been attempted is to bore small holes into the width of the lens material and insert rods or dowels therein to allow the lens to be handled without physically touching the lens itself. However, where a hard optical material is used, such as a thermoset plastic, it is difficult to bore into the lens without fracturing or splitting the lens element. Similarly, attempts have been made to affix handling means onto a lens by the use of an adhesive substance. Once again, these attempts have met with little success inasmuch as the adhesive typically does not retain its adhesion characteristics during the coating process. In addition, problems of contamination may arise where adhesives are used, since the adhesive material may partially dissolve into the coating mixture thereby contaminating it.
Accordingly, there exists a need for a simple, reliable and cost effective device to handle and convey optical lenses and the like during the various manufacturing and coating processes.
A primary object of the present invention, therefore, is to provide a means by which optical materials can be handled and conveyed during the manufacturing and coating process. A secondary object is to provide a means capable of handling optical materials of a variety of sizes and dimensions without modification to the handling means. An additional object of the invention is to provide a handling means for optical materials which is essentially inert and non-reactive with the various coating processes and mixtures used in the art.